Beattie was released by Sheffield United in the summer but is linking up with new Stanley boss Leam Richardson, his old Blackburn team-mate.
The five-cap England international, 34, only has a deal until January but is itching to get going.
Beattie said: "I'm delighted to be here and can't wait to get started.
"The coaching role has put another angle on things but I've signed a playing contract so I want to get involved as soon as I can."
Richardson said: "My relationship with James goes back a long way.
"Throughout his career, he's been fantastic. He's a great pro and for him to come to Stanley is a massive boost for the club."